Create a SpatRasterDataset

Methods to create a SpatRasterDataset. This is an object to hold "sub-datasets", each represented by a SpatRaster that may have multiple layers. All sub-datasets must have the same raster geometry (extent and resolution). You can use a SpatRasterCollection (see sprc) to combine SpatRasters with different geometries.

See describe for getting information about the sub-datasets present in a file.

Usage

# S4 method for class 'missing'
sds(x) 

# S4 method for class 'character'
sds(x, ids=0, opts=NULL, raw=FALSE, noflip=FALSE, guessCRS=TRUE, domains="", md=FALSE)

# S4 method for class 'SpatRaster'
sds(x, ...) 

# S4 method for class 'list'
sds(x) 

# S4 method for class 'array'
sds(x, crs="", extent=NULL)

Arguments

x

character (filename), or SpatRaster, or list of SpatRasters, or missing. If multiple filenames are provided, it is attempted to make SpatRasters from these, and combine them into a SpatRasterDataset

ids

optional. vector of integer subdataset ids. Ignored if the first value is not a positive integer

opts

character. GDAL dataset open options

raw

logical. If TRUE, scale and offset values are ignored

noflip

logical. If TRUE, a raster (e.g. JPEG image) that is not georeferenced and that GDAL assigns a flipped extent to (ymax < ymin), is not considered flipped. This avoids the need to flip the raster vertically

guessCRS

logical. If TRUE and the file does not specify a CRS but has an extent that is within longitude/latitude bounds, the longitude/latitude crs is assigned to the SpatRaster

domains

character. Metadata domains to read (see metags to retrieve their values if there are any). "" is the default domain

md

logical. If TRUE, the multi-dimensional GDAL API is used for reading the file. This API can only be used for a few file formats (netCDF/HDF5) and can sometimes provide notably faster reading of data with many (time) steps in the third or higher dimension. If no subdataset is selected with subds, all usable arrays are combined into one SpatRaster (like md=FALSE); a warning reports how many variables and layers were combined when there is more than one variable.

crs

character. Description of the Coordinate Reference System (map projection) in PROJ.4, WKT or authority:code notation. If this argument is missing, and the x coordinates are within -360 .. 360 and the y coordinates are within -90 .. 90, longitude/latitude is assigned

extent

SpatExtent

...

additional SpatRaster objects

Value

SpatRasterDataset

See also

sprc, describe

Examples

s <- rast(system.file("ex/logo.tif", package="terra"))   
x <- sds(s, s/2)
names(x) <- c("first", "second")
x
#> class       : SpatRasterDataset
#> subdatasets : 2
#> dimensions  : 77, 101 (nrow, ncol)
#> nlyr        : 3, 3
#> resolution  : 1, 1  (x, y)
#> extent      : 0, 101, 0, 77  (xmin, xmax, ymin, ymax)
#> coord. ref. : Cartesian (Meter)
#> source(s)   : logo.tif, memory
#> names       : first, second
length(x)
#> [1] 2

# extract the second SpatRaster
x[2]
#> class       : SpatRaster
#> size        : 77, 101, 3  (nrow, ncol, nlyr)
#> resolution  : 1, 1  (x, y)
#> extent      : 0, 101, 0, 77  (xmin, xmax, ymin, ymax)
#> coord. ref. : Cartesian (Meter)
#> source(s)   : memory
#> varname     : logo
#> names       :   red, green,  blue
#> min values  :     0,     0,     0
#> max values  : 127.5, 127.5, 127.5

a <- array(1:9, c(3,3,3,3))
sds(a)
#> class       : SpatRasterDataset
#> subdatasets : 3
#> dimensions  : 3, 3 (nrow, ncol)
#> nlyr        : 3, 3, 3
#> resolution  : 1, 1  (x, y)
#> extent      : 0, 3, 0, 3  (xmin, xmax, ymin, ymax)
#> coord. ref. : 
#> source(s)   : memory